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Batch sparging...no mashout...low FG?

I’ve been batch sparging for a year or so now, and about 6 months ago, I quit doing mashouts. I just increased my strike water ratio so I got enough wort in 1st runnings. I had read some threads about guys saying the mashout isn’t necessary. It’s saved me some time, so I thought it was great. I sparge with 190F water. Most mashes are 153F and hold temps fairly well.

I’ve noticed I’ve been getting some very low final gravities lately. My last pale ale finished at 1.004. Way lower than I want. I lot of beers are finishing in the 1.005-1.007 range.

I’ve been beating myself up trying to figure out what the problem is. The beers taste good, so not infected. Fermentation temps are controlled and usually 66-68.

After some recent reading, I came up with the idea that maybe because I wasn’t doing a mashout, raising the grain bed temp and not stopping enzyme activity, maybe that was the cause. Normally after my 1st runnings, I start the heat on the burner, though.

Anyone have any thoughts on this? Could not doing a mashout be the cause of my low FG’s, or do I need to keep looking elsewhere?

Cheers!

I can’t imagine it hs anything to do with no mashout. Since you batch sparge, you get to a boil quickly which denatures enzymes better than a mashout. I think you should start by making sure your thermometer is correct and you’re mashing at the temp you think you are.

Have you calibrated your hydrometer/refractometer recently?

I checked my thermometer in ice water and boiling water and it’s accurate. My hydrometers are the lab grade ones NB sells, and I’ve checked them to be sure.

I’ll have to start looking elsewhere in my system to see what the problem is. Fermentation seems to take a long time. Over a week of active fermentation. Lag time is usually less than 12 hours. I always do starters. My aeration could be better, but I don’t think it’s real bad.

[quote=“CCM”]I checked my thermometer in ice water and boiling water and it’s accurate. My hydrometers are the lab grade ones NB sells, and I’ve checked them to be sure.

I’ll have to start looking elsewhere in my system to see what the problem is. Fermentation seems to take a long time. Over a week of active fermentation. Lag time is usually less than 12 hours. I always do starters. My aeration could be better, but I don’t think it’s real bad.[/quote]

Unless you mash at 32 or 212 degrees, checking a tehrmometer that way doesn’t really tell you anything. It could still be off at mash temps. I’ve seen it more than once.

[quote=“Denny”]

Unless you mash at 32 or 212 degrees, checking a tehrmometer that way doesn’t really tell you anything. It could still be off at mash temps. I’ve seen it more than once.[/quote]

Fair enough…what’s the best way to check at mash temps? I used freezing and boiling because they are known temps that I don’t have to rely on other thermometers to measure, as the other thermometers could be off, too.

[quote=“CCM”][quote=“Denny”]

Unless you mash at 32 or 212 degrees, checking a tehrmometer that way doesn’t really tell you anything. It could still be off at mash temps. I’ve seen it more than once.[/quote]

Fair enough…what’s the best way to check at mash temps? I used freezing and boiling because they are known temps that I don’t have to rely on other thermometers to measure, as the other thermometers could be off, too.[/quote]

I use a certified, calibrated lab thermometer to calibrate my brewing thermometers at 150F.

[quote=“Denny”]

I use a certified, calibrated lab thermometer to calibrate my brewing thermometers at 150F.[/quote]

I’ll add that to my shopping list. Is the one NB sells, their “lab thermometer” for $6.99 actually a calibrated one, or is there a better place to get one?

BTW, thanks for the info, Denny.

[quote=“CCM”][quote=“Denny”]

I use a certified, calibrated lab thermometer to calibrate my brewing thermometers at 150F.[/quote]

I’ll add that to my shopping list. Is the one NB sells, their “lab thermometer” for $6.99 actually a calibrated one, or is there a better place to get one?

BTW, thanks for the info, Denny.[/quote]

I got mine from William’s brewing, but they no longer sell it. At $6.99 I doubt the one you’re looking at is NIST certified. Maybe take a look at the VWR website. It’ll probably run $30 or so.

I do mostly no-sparge or batch sparge and my own experience is that a mashout will add to efficiency and add 5pts to the FG. That said I don’t have unusually low FGs they are where I put them based on recipe and mash temp/time.

Lennie, do you check your conversion efficiency?

[quote=“Denny”][quote=“CCM”]I checked my thermometer in ice water and boiling water and it’s accurate. My hydrometers are the lab grade ones NB sells, and I’ve checked them to be sure.

I’ll have to start looking elsewhere in my system to see what the problem is. Fermentation seems to take a long time. Over a week of active fermentation. Lag time is usually less than 12 hours. I always do starters. My aeration could be better, but I don’t think it’s real bad.[/quote]

Unless you mash at 32 or 212 degrees, checking a tehrmometer that way doesn’t really tell you anything. It could still be off at mash temps. I’ve seen it more than once.[/quote]

For a good many years I worked in the food industry. All of the Ashcroft dial thermometers that were used in various departments used a standard ice bath and a boiling water bath.It’s quite obvious to us that the water boiled at a different temp due to the altitude that the plant was at. Both bathes used a glass thermometer as a set parameter. The dial thermometers were then calibrated to the glass thermometer. Because of the temperature accuracy involved, all of the product makers had to sign off on a thermometer check list at the beginning of their shift inside the company’s lab.The lab supervisor would come over and watch us. I didn’t mind her watching because I wanted to help produce fine products for the company. Working foremen would check these thermometers quite often during a 9 hour shift. As a homebrewer, I use the same practice as I was taught at work to calibrate my dial thermometer.

I really don’t see the basis for you writing that.

The basis for me writing that is the experience of myself and many others. When I try something and it doesn’t work several times with several different thermometers, I can’t recommend the technique. When I hear of other people having the same experience, it reinforces it.

It’s simple, you just can’t be right all of the time.

It’s simple, you just can’t be right all of the time.[/quote]

Are you saying he is, in fact wrong, just because you don’t agree?

It’s simple, you just can’t be right all of the time.[/quote]

Are you saying he is, in fact wrong, just because you don’t agree?[/quote] I would say they don’t agree with each other.

I frequently do a ballpark calculations by hand and am getting right around 75% consistently so that is what I use to design my recipes. I do tend to let a mash go 90min or so, especially with no sparge.

It’s simple, you just can’t be right all of the time.[/quote]

How can I be wrong about my own experience?

What pH are you mashing at? If you are on the lower side of things you might be getting more beta activity regardless of temp… This something I am working on lately since my fg are a bit lower than I want as well.

I just checked my digital thermometer with a NIST certified one I bought. It checked out at 32, 153, 170 and boiling.

My Ph is probably around 5.7 usually, although I don’t check. That is based on Brun Water. I’m starting to do more adjustments to my water to bring it closer to 5.4ish, based on Brun.

I’m brewing two back to back batches of the same pale ale tomorrow. I’m going to do some water adjustments on one, but not the other and see what the end result difference will be. Maybe that will be my low FG problem.

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